added code to restrict deletion of relationship

deleterelationshipperm.php

@@ -133,3 +133,72 @@ function deleterelationshipperm_civicrm_alterSettingsFolders(&$metaDataFolders =
 function deleterelationshipperm_civicrm_entityTypes(&$entityTypes) {
   _deleterelationshipperm_civix_civicrm_entityTypes($entityTypes);
 }
+/**
+ * Implements hook_civicrm_permission().
+ *
+ * @link http://wiki.civicrm.org/confluence/display/CRMDOC/hook_civicrm_permission
+ */
+function deleterelationshipperm_civicrm_permission(&$permissions) {
+  $prefix = ts('CiviCRM') . ': ';
+  $permissions['delete relationships'] = [
+    $prefix . ts('Delete relationships'),
+    ts('Delete contact relationships'),
+  ];
+}
+
+/**
+ * Implements hook_civicrm_links().
+ *
+ * @link http://wiki.civicrm.org/confluence/display/CRMDOC/hook_civicrm_links
+ */
+function deleterelationshipperm_civicrm_links($op, $objectName, $objectId, &$links, &$mask, &$values) {
+  if ($op == 'relationship.selector.row' && $objectName == 'Relationship') {
+    if (!CRM_Core_Permission::check('delete relationships')) {
+      foreach ($links as $key => $link) {
+        if ($link['name'] == 'Delete') {
+          unset($links[$key]);
+        }
+      }
+    }
+  }
+}
+
+/**
+ * Implements hook_civicrm_pre().
+ *
+ * @link http://wiki.civicrm.org/confluence/display/CRMDOC/hook_civicrm_pre
+ */
+function deleterelationshipperm_civicrm_pre($op, $objectName, $id, &$params) {
+  if ($op == 'delete' && $objectName == 'Relationship') {
+    _deleterelationshipperm_civicrm_check_permission();
+  }
+}
+
+/**
+ * Implements hook_civicrm_apiWrappers().
+ *
+ * @link http://wiki.civicrm.org/confluence/display/CRMDOC/hook_civicrm_apiWrappers
+ */
+function deleterelationshipperm_civicrm_apiWrappers(&$wrappers, $apiRequest) {
+  if ($apiRequest['entity'] == 'Relationship' && $apiRequest['action'] == 'delete') {
+    _deleterelationshipperm_civicrm_check_permission('exception');
+  }
+}
+
+/**
+ * Check if user has permission to delete relationship.
+ *
+ * @param string $errorType
+ */
+function _deleterelationshipperm_civicrm_check_permission($errorType = NULL) {
+  if (CRM_Core_Permission::check('delete relationships')) {
+    return FALSE;
+  }
+  $message = ts('You do not have the necessary permission to delete this relationship.');
+  if ($errorType == 'exception') {
+    throw new API_Exception($message);
+  }
+  else {
+    CRM_Core_Error::statusBounce($message);
+  }
+}